Toggle-operated, locking pliers have been available commercially for many years. Some toggle-operated, locking pliers are of a size for use in plumbing for connecting and disconnecting pipes and pipe fittings. Other toggle-operated, locking pliers have been designed for special purposes with specially designed clamps or jaws.
Belval U.S. Pat. No. 3,290,971 discloses a toggle-operated, locking pipefitters tool with specially designed clamps or jaws with spaced rods for handling different sized pipes and pipe fittings.
Lock U.S. Pat. No. 3,578,307 discloses a toggle-operated, pipe wrench.
Nunez U.S. Pat. No. 3,718,327 discloses a C-clamp with toggle-operated, locking tools secured thereon for positioning and supporting a workpiece.
Fideldy U.S. Pat. No. 3,884,100 discloses a pipe tongs with toggle-operated, locking action and having specially designed "C" jaws for handling pipes of selected sizes.
Guilliams U.S. Pat. No. 4,318,316 discloses toggle-operated, locking pliers with specially designed clamps or jaws for handling threaded hanger rods without damaging threads.
Dearman U.S. Pat. No. 4,344,215 discloses a toggle-operated, locking pipefitters tool with specially designed "V" clamps or jaws for handling different sized pipes and pipe fittings.
Costello U.S. Pat. No. 4,477,937 discloses a combined wrench, locking pliers and chain wrench using a toggle for the gripping and clamping functions.
This invention is an improvement over the prior art pliers and tongs in that it consists of a fixed handle with a removable pipe clamp at one end thereof and an adjustment screw at the other end, and a movable jaw member with a removable pipe clamp at one end thereof, a movable handle connected to the movable jaw member at one end and having a latch with an operating lever at the other end. A linkage is connected between the movable handle and the adjustment screw to provide an adjustable toggle or locking mechanism for the handles and movable jaw member of the tongs; a latch on the fixed handle is engaged by a catch to secure the movable handle in a locked, closed position; the removable pipe clamps are provided in a variety of sizes and shaped for accommodating different pipes; and the pipe tong handles have projections beyond the point of support for the pipe clamps which provide a means to support the tongs on a well casing and to support a wire or cable spaced from the wall of the well casing while lowering pipe into the casing.